Researchers Cooperate on PCV2 Immunity
EU - T. Kekarainen of the Autonomous University of Barcelona and co-authors from across Europe have publised a paper in Veterinary Immunology and Immunopathology on immune responses and vaccine-induced immunity against porcine circovirus type 2 (PCV2).Their review focuses on the recent research on immunological aspects during PCV2 infections and summarises what is currently known about the vaccine-induced immunity.
PCV2 is essential but not sufficient for post-weaning multisystemic wasting syndrome (PMWS) occurrence in pigs, they explain. The outcome of PCV2 infection depends on the specific immune responses that are developing during the infection.
Diseased pigs are immunosupressed and unable to mount effective immune responses to clear the virus from circulation. In the final stage, PMWS-affected pigs suffer from extensive lymphoid lesions and altered cytokine expression patterns in peripheral blood mononuclear cells (PBMCs) and lymphoid organs. PCV2 infection can also be asymptomatic, demonstrating that not every infection will guarantee the occurrence of severe immunopathological disturbances. Asymptomatic animals have higher virus specific and neutralising antibody titres than PMWS-affected animals.
Recent results have pointed out that the mechanisms by which PCV2 can affect the immune responses involve the induction of IL-10, virus accumulation into and modulation of plasmacytoid dendritic cells and the role of viral DNA in regulation of immune cell functions.
Fourteen years after the first description of PMWS in Canada, efficient commercial vaccines against PCV2 are available. The vaccine success is based on activated humoral and cellular immune responses against PCV2.
Reference
Kekarainen T., K. McCullough, M. Fort, C. Fossum, J. Segalés and G.M. Allan. 2010. Immune responses and vaccine-induced immunity against Porcine circovirus type 2. Veterinary Immunology and Immunopathology, 136 (3-4): 185-193. doi:10.1016/j.vetimm.2010.03.025.
Further Reading
- | Find out more information on Post-Weaning Multisystemic Wasting Syndrome (PMWS) by clicking here. |